Electro-optic devices, and especially poled hyperpolarizable organic chromophore-based electro-optic devices have typically been limited to using hybrid organic-inorganic cladding materials that have a relatively high index of refraction. For example, a crosslinked hybrid organic-inorganic silicon sol-gel may have an index of refraction of 1.45 to 1.47 at a wavelength of 1550 nanometers (nm). Other crosslinked hybrid organic-inorganic sol-gels made from titanate, aluminate, or zirconate precursors have also typically had respective indices of refraction that are substantially determined according to the particular type of sol-gel (i.e. titanium, zirconium, or aluminum-based).